The present invention relates in general to driver vision systems, and, more specifically, to a rear view camera system using an external camera with a large field of view together with an internal camera and display providing contextual information to the driver.
Conventional vision aids enabling a driver to monitor the surroundings behind and to the side of a vehicle include externally-mounted side view mirrors and an internally-mounted rear view mirror. Mirror placement and shapes have been manipulated in attempts to minimize blind spots. Due to the many tradeoffs between mirror field of view, mounting locations, and interference by other solid vehicle structures, blind spots may still occur. For example, a trend toward increased head rest size has resulted in increased blocking of the rearward view from the center-located rear view mirror. The view through the rear view mirror may also be obscured by temporary objects in the interior such as rear seat passengers and cargo or by glare from headlamps of other vehicles. In addition, vehicle size and/or styling considerations may result in the use of relatively small back windows through which the rear view mirror obtains the exterior view. Regardless of window size, the buildup of dirt, frost, or snow which may sometimes occur on the back window may obscure the view obtained with the rear view mirror.
Backup cameras with a live video display presented on the instrument panel or dashboard have been introduced to alleviate some of these problems. Typically, the image from a backup camera is horizontally flipped for display on the video screen in order to give the driver a mirror image (i.e., since the driver is looking in the opposite direction from the camera, the image is flipped so that left and right in the displayed image correspond with the driver's left and right). The reverse-view display screen is activated while in reverse gear to help the driver check for any objects in their backup path, but it is typically deactivated during forward driving since the video can be distracting or may be confusing to the driver because of possible difficulties in integrating the reverse camera view into their mental frame of reference of the surroundings.